Continuous vulcanizer



F. B. DE HAAN CONTINUOUS VULCANIZER Filed April 24, 1957 Oct. 13, 1959 a. NM

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'United States Patent CONTINUOUS VULCANIZER Fred B. De Haan, Paterson, N .J., assignor to The Okonite Company, Passaic, N.J., a corporation of New Jersey Application April 24, 1957, Serial No. 654,760

2' Claims. (Cl. 186) My invention relates to an improvement in vulcanizers of the continuous type wherein the vulcanizable covers of articles, such as electric wires and cables, may be, con: tinuously vulcanized.

One of the objects of my invention is to provide a construction whereby the wire or cable may be introduced into the vulcanizing tube and continuously. discharged therefrom in a more satisfactory fashion than possible with existing conventional equipment.

In general, my improved vuleanizer comprises along, cylindrical tube, eighty or more feet in length. Dry steam is admitted to this tube intennediateitsends and prevented from escaping at the tube ends by a water seal. The wire or cable to which the. cover to bevulcanized has already been applied is continuously advanced through the tube. The steam is maintained at apressure of-one hundred pounds per square inch, or higher, and the-interior of the tube is raised to a temperature. of around 330 F. Thus, by regulating the rate. at which the covered wire or cable is advanced through the tube, the exposure to curing temperature and, consequently, the degree of vulcanization can be controlled.

Prior to my invention a definite problem existed with respect to the introduction of the wire or cable into the vulcanizing tube and its discharge from the exit end of the tube. Normally, a metal plate is emplaced over the tube ends to retain the water seals. inside the tube. As the wire or cable is drawn through the tube, this plate must be withdrawn to allow the wire or cable to pass out of the tube. The wire or cable fits into a circular opening at the tube ends, thus preventing the escape of water. However, in the short interval of time between the removal of the plate and the entry of the cable into the circular opening, the steam pressure is acting upon one end of the water seal, while the other end of the seal This creates an unbalance in the system and a consequent temperature drop. This has an unfavorable effect upon the curing of the covering of the wire or cable, since some time must elapse before return to stable operation. The properties displayed by the covering being vulcanized will vary accordingly, and an unsatisfactory product results.

My invention provides against such conditions and embodies a construction whereby the covered wire or cable enters into and exits from the vulcanizing tube without detrimental loss of water and without disrupting the balanced conditions existing within the vulcanizing tube; the only water which is allowed to escape is a very slight amount just about the wire or cable which functions as a lubricant.

In the accompanying drawings, wherein I have illustrated an embodiment of my invention,

Fig. 1 is a sectional view taken at the discharge end of my improved vuleanizer; and

Fig. 2 is an elevational view of the vuleanizer.

Referring to the drawings in detail, 2 designates a vulcanizing tube, which is a long, cylindrical tube, eighty feet in length, for example, and, say, eight inches internal Patented Oct. '13, 1959 2 diameter. These dimensions: are purely by way of illustration.

Provision is made about midway of the length of the vulcanizing tube, as illustrated at 4, for admitting dry steam to the tube interior. This steam may be at apressure of the order of one hundred pounds per square inch. Adjacent each end of the tube 2 means are provided, designated 6, for admitting water under pressure from any suitable source to the tube interior at each end of the steam charge, thereby to provide a water seal for the steam. 8 designates a steel housing ateach end of the vulcanizing tube 2, this housing acting. as a holder for an aluminum bushing 10 (see Fig. 1). Each bushing is held in place by a steel retainingring 12. The ring. is held in place by cap screws 14, which pass into the housing 8 through keyhole slots in the ring to permit the ringto be removed without the necessity of removing the screws. Each vof the. housings 8 is provided with an internal annulargroove 11, and lying within each of these grooves is aninflated ring. gasket 13 for preventing. the escape of water along the exterior of the bushing.

Each of therings-12is provided with an extension tube 16. Each tubefits into itsv ring and: projects fifteen inches, moreor less, beyond. the outer face. of the ring; Each extension tube is provided at its outerend with a coverv plate 18,. provided with a radialslot20; Each cover, plate is carried by an arm 22,; fulcrumedat 2.4, and operated. from an air. cylinder 26.

Immediately back. of each of the bushings 10- are. seal-. ing diaphragms 281 These are of neoprene, forexample, and 'act as waterguards and provide for somevariation; in wire or cable outside. diameter. Afilm of Water-is-al-r lowed to How between the diahpragms and the wire or cable, to lubricate the wire or cable and to avoid chafing. Within each housing 8, between an internal shoulder 9, with which each housing is provided, and the sealing diaphragms 28, is a belled steel ring 30, which rings prevent displacement of the diaphragms and facilitate entry of the wire or cable.

The wire or cable the cover of which is to be vulcanized has been designated 32. Fig. 1 is taken at the discharge end of the vuleanizer, and it will be seen from this view that the leading end of the wire or cable is equipped with a pulling eye 34, to which is attached a pulling line 36. In commercial operation the wire or cable will be drawn through the vuleanizer from a let-off reel at one end of the vuleanizer and, after passing through the vuleanizer, will be rewound upon a take-up reel at the discharge end of the vuleanizer.

In operation, the pulling line 36 is first threaded through the vuleanizer until its leading end projects from the outer end of the extension tube 16 at the discharge end of the vuleanizer. The slot 20 permits the cover plates at each end of the vuleanizer to be closed at that time. The pulling line is drawn through the vuleanizer until the leading end of the wire or cable 3 2 enters the seal at the entry end of the vulcanizing tube 2, the plate 18 at the entry end of the vuleanizer being raised to permit passage of the wire or cable. With the steam and water on in the vulcanizing tube, the wire or cable is drawn through the tube until the leading end of the wire or cable has entered the seal at the exit end of the vulcanizing tube, as illustrated in Fig. 1. During the passage of the wire or cable to this position, the cover plate at the discharge end of the vuleanizer is kept closed; hence, no water can escape at this end of the vuleanizer to a detrimental extent. Water is prevented from escaping at the entry end of the vulcanizing tube by the diaphragms 28. When the wire or cable reaches the position illustrated in Fig. 1, then the cover plate 18 at the exit end of the vuleanizer can be opened to permit the wire or cable to pass through the extension tube 16 at that end of the vulcanizer. As the leading end of the wire or cable emerges from the exit extension tube 16, the pulling line 36 is removed, and the end of the wire or cable is made fast to the takeup reel. The trailing end of the wire or cable is equipped with a light line, which is used to draw the pulling line back through the vulcanizer as each length of wire or cable has been vulcanized, so that the pulling line may be attached to the next length which is to be drawn through the vulcanizer.

It will be seen from the foregoing that with my improved apparatus provision is made for vulcanizing the entire length of wire or cable in that, from the time the leading end of a length enters the seal at the entry end of the vulcanizer until the trailing end of the length is discharged, the vulcanizer is sealed against detrimental loss of water, and disruption of equilibrium of the system is avoided, so that uniformity of cure is assured.

It is to be understood that changes may be made in the details of construction and arrangement of parts herein above described within the purview of my invention.

What I claim is:

l. A vulcanizer for the continuous vulcanizing of the covering of long lengths of electric cable, said vulcanizer comprising, in combination, an elongated, cylindrical tube; means for supplying dry steam to the tube interior intermediate the tube ends; means for supplying water to the tube interior adjacent each end of the tube, thereby to provide a water seal for the said steam; sealing means at each end of the tube positioned to cooperate with the cable being vulcanized, as the cable advances through the tube, for sealing the tube ends against deleterious water leakage from the tube; an extension tube on each end of the main tube; a cover plate for the outer end of each of said extension tubes provided with an opening for the passage of a pulling line by which the cable is initially advanced through the vulcanizing tube, said cover plates preventing the escape of water from the apparatus to a deleterious extent until the cable has been advanced sufliciently to have entered the said sealing means at the tube ends, the sealing means co-acting with the cable thereafter to continue the sealing action.

2. A vulcanizer for the continuous vulcanizing of the vulcanizable covering of electric wires and cables, said vulcanizer comprising, in combination, an elongated, cylindrical tube through which the article to be vulcanized is continuously advanced; means for supplying dry steam to the tube intermediate the tube ends; means for supplying water to the tube interior adjacent each end of the tube to provide a water seal for the steam; a housing afiixed to each end of the tube; a metal bushing set into each of said housings, the bore of each bushing being in alignment with said tube; a ring for holding each of said bushings in place in the housing; an extension tube at each ring coaxial with the first-mentioned tube, one end of each of said extension tubes abutting the inner peripheral surface of a ring, the remaining portion of each extension tube extending beyond the plane of the ring;

References Cited in the file of this patent UNITED STATES PATENTS 1,610,954 Lamplough Dec. 14, 1926 2,307,575 Davis Jan. 5, 1943 2,589,713 Lawrence Mar. 18, 1952 2,789,314 Davis Apr. 23, 1957 

